Converting a mammography facility from film-screen to digital involves more than just the purchase of new acquisition equipment. Attention needs to be devoted to the impact on image quality, workflow and efficiency of all components involved, including:

• Workstations
• Archives or PACS
• Film printers
• Reporting and information systems
• Film digitizers

These concerns are as applicable to small stand-alone facilities as they are to large hospitals with general-purpose PACS systems.

Q: Why do I need to be concerned about integrating multiple vendors’ equipment?

A: It’s unlikely that a single vendor will provide the entire solution (acquisition, display, reporting, scheduling, archiving, distribution, export and printing). Also, as digital mammography becomes widespread, prior images will often be received on CDs which were most likely created on another vendors’ equipment.

Q: But all the equipment claims to conform to DICOM and HL7. Is that not sufficient?

A: While the DICOM and HL7 standards provide the technical basis for connecting systems, they don’t define the higher levels of system interaction and workflow that support users’ clinical needs.

Q: Why can’t I just read my digital mammograms on my existing general-purpose PACS?

A: Efficient mammography reading requires specific display quality, behavior, layout and annotation of images, as well as convenient comparison of prior with current images. To date, these features have typically only been available in dedicated workstations, as many general-purpose PACS and third-party workstations have lacked mammography-specific features. The IHE Mammography Image Profile (IHE Mammo) was developed specifically to define the necessary mammography requirements.

Q: Will my digital mammograms from one vendor display properly on another vendor’s workstation or PACS?

A Without IHE Mammo features, problems typically encountered include achieving the proper orientation, comparable size of current and prior images (below), justification to the chest wall, consistency of grayscale contrast (window) settings and completeness of annotations. IHE Mammo not only clarifies what values must be put in DICOM images by the modality, but also which values are to be used by the workstation.

Q: What about integrating CAD?

A: IHE Mammo requires all workstations to be capable of displaying CAD marks encoded using the appropriate DICOM standard. However, it does not define an “official” workflow for CAD. For that reason, the current industry-standard methods will be utilized in the mean time. CAD integration will be addressed in the next year of IHE development.





Q: How can I display priors received on a CD from another facility at my workstation or import them into the PACS or burn images to a CD to send to another facility?

A: The IHE Portable Data for Imaging (PDI) profile defines the use of DICOM-standard CDs for the interchange of images, and can be requested in addition to the IHE Mammo profile.

Q: How can I archive my images for future use as priors or for legal retention reasons?

A: DICOM-standard mammography images can be stored on most PACS and archive systems, or a small dedicated archive can be used. This is part of the IHE Mammo profile.

Q: How can I print images from my digital system that are of primary diagnostic quality and are appropriately annotated?

A: IHE Mammo adapts the existing IHE printing mechanisms for mammography. It adds printing true-size, annotations appropriate for mammog-raphy, alignment of images at the edge of the film, and correct mammographic grayscale appearance.

Q: How can I achieve consistency of appearance of images on different displays?

A All DICOM digital mammography images are already encoded with the intent that they be dis-played on monitors that are calibrated in a stan-dard way. This is a prerequisite for the IHE Mammo and Consistent Presentation of Images (CPI) profiles. However, achieving consistent display across different technologies (LCD versus CRT) remains a challenge, and requires attention to the consistent settings of primary diagnostic displays in the same institution, as well as control of ambient lighting conditions.

Q: How can I be sure that patients and exams will be correctly identified across all the systems and scheduled appropriately, that patient data entry at the modality is avoided, and that images reach their intended destinations?

A: The IHE Scheduled Workflow (SWF) profile specifies the use of DICOM Modality Worklist as well as other services to provide accurate and complete information from the information system to the modality and subsequent status back to the information system or PACS.

Q: How can I purchase digital equipment now, or upgrade existing equipment, with the IHE Mammography Image profile being so new?

A: A strong commitment has been expressed by many vendors to support the IHE profiles, so it should be possible to negotiate a purchase or maintenance contract that includes a requirement to upgrade any new or installed product within a specified, reasonable time, to conform to the required profiles.